If you’re a Catholic Constantine was a great guy, if a Jew or Sabbatarian, not so much. He enforced Sunday worship. He was the first to make the original “blue” laws with his codexs. Politics and religion should not mix, even if he was on your side. That is between an individual and God.
Constantine never enforced any “Sunday worship”. He prescribed that townspeople, but not farmers, obey a day of rest on Sunday. That’s all.